The invention relates to an ink-jet ink containing a sublimation dye component in conjunction with an additional non-sublimation colorant, and further to the use thereof in a process for preparing a dye sublimation ink-jet ink transfer intended for use in secondary transfer operations or processes.
There is a large market for transfer printing. By xe2x80x9ctransfer printingxe2x80x9d is meant the transfer of an image, whether in the form of a photograph, a computer generated picture or a graphic design, words, such as a company logo or a particular saying, or other type of printed matter. Generally, transfer printing involves producing a transfer sheet or substrate bearing the image to be transferred, and subsequently transferring the image from the transfer sheet or substrate to a permanent substrate upon which the image is to permanently appear. The permanent substrate may be any type of material which will accept and retain the transferred image, including but not limited to fabric, including natural fiber materials, synthetic materials, and combinations thereof, wood, glass, ceramic, metal, and other such substrates. Most often, transfer printing is used to generate such items as t-shirts, coffee mugs, mouse pads, and other such items. The process may also be used to print security-type items, such as identity badges.
Prior art technology provides for printing a full color image, usually in the reverse format, on a transfer sheet. This allows the user to view the final image, even if in reverse format, and even though the colors may be to some extent dull. Having the permanent image visible on the transfer or intermediate substrate may not be desirable in those instances where security is an issue, such as in the printing of identity badges or other security-type information.
Known transfer processes employ inks containing sublimable or diffusion-type dyes, sometimes called xe2x80x9cheat activatedxe2x80x9d dyes or colorants. These dyes are well suited to the transfer industry due to the fact that they activate or diffuse only at elevated temperatures, in the range of about 300xc2x0 C. to 450xc2x0 C. Therefore, the operational temperature of most printers will not activate the dye, and the dye merely prints onto the transfer substrate but is not permanently bound thereto. A subsequent application of heat and/or pressure is used to xe2x80x9ctransferxe2x80x9d the dye previously printed in the desired image on the transfer substrate, to the permanent substrate, i.e., a combination of elevated temperature and pressure cause the dye to activate and diffuse into the permanent substrate surface where it permanently bonds. The temperature and pressure parameters are dictated by the sublimation dye used, by any additional components in the ink which interfere with or inhibit the diffusion of the sublimation dye, and by the substrate itself upon which the final image is formed.
Prior technology used ribbons to carry the sublimation dye-containing inks. More recent printers require the use of liquid inks. With either print set-up, the printed transfer substrate, or intermediate substrate, is printed such that the image to be transferred is visible and substantially consistent with the permanent transferred image.
Inkjet printers using liquid inks are usually fitted with stations to accept color or color and black cartridges. The color cartridges may jet cyan, magenta, and yellow ink droplets. The black cartridge jets black ink droplets. Full color images are printed by jetting combinations of the color inks (referred to as subtractive primary colors). For example, red is printed with a combination of magenta and yellow inks; green is printed with a combination of cyan and yellow inks; and blue is printed with a combination of cyan and magenta inks. Virtually any color may be printed by printing appropriate amounts of the subtractive primary colors. Black is generally printed with a combination of the three colors. The black cartridge is used to print text and to add black density to the shadows in full color printed images. This type of processing, when used to create transfer sheets, can only generate an intermediate image which is visually the same with regard to color as the final image once transferred. Generally, a computer program is required to print the intermediate image in the reverse of the final image, so that upon transfer the image is appropriately situated. This, however, is unacceptable in those instances, such as in the printing of security items, where there is a need for the permanent image to be revealed only on the permanent substrate.
Therefore, there exists a need in the industry for a means to print an intermediate transfer substrate that does not reveal the image to be transferred to the permanent substrate prior to the transfer.
It is an object of the invention to provide an ink-jet ink suitable for use in current inkjet printers and which prints a monochrome intermediate transfer substrate which may subsequently be used to transfer a multi-color image to a permanent substrate.
It is another object of the invention to provide an ink-jet ink composition which contains a first sublimation-type colorant and a second non-sublimation type colorant, wherein the second non-sublimation type colorant functions to mask on a printed intermediate substrate the full color image which is to be ultimately rendered on a permanent substrate.
It is yet another object of the invention to provide an ink-jet ink composition suitable for use in generating an intermediate substrate which may be used to render a full color image on a secondary or permanent substrate, wherein the ink-jet ink composition comprises a first sublimable colorant and a second non-sublimable colorant, and wherein the second non-sublimable colorant is a colorant capable of absorbing and retaining heat generated during printing of the intermediate substrate, thus lowering the amount of heat necessary to affect sublimation of the first sublimable colorant upon transfer to the permanent substrate.
It is still another object of the invention to provide a process for printing a monochrome intermediate substrate which may subsequently be used to render a full color image on a permanent substrate.
It is another object of the invention to provide a process for printing a monochrome intermediate substrate which may subsequently be used to render a full color image on a permanent substrate wherein the process includes the use of an ink-jet ink composition which comprises at least a first sublimable colorant and a second non-sublimable colorant and wherein the full color image rendered on the permanent substrate is transferred from a monochrome intermediate substrate at a temperature lower than the normal sublimation temperature of the first sublimation colorant.